Transcript Ch 2 BIO Notes

Organic / Biochemistry
Chemistry of Life!
Biology
Chapter 2
Carbon Compounds in Cells!
Subatomic parts
• PROTONS – Positive charged particles
found in the nucleus of an atom.
• NEUTRONS – neutral charge (no charge)
particles found in the nucleus.
• ELECTRONS – Negative charged particles
found outside the nucleus of the atom.
– These determine which elements interact with each
other!
ELEMENTS
• Pure substance made of the same type
atoms.
• Periodic Table of the Elements – over 100
“pure” substances found in the universe
• Hydrogen has 1 proton and 1 electron.
BONDS
• Ionic Bonds – When two ions are attracted
by opposite charges (they either DONATE
or TAKE an electron)….. Ex Salt
• Sodium ion Na+ -----Chlorine ions Cl• NaCl
Bonds Cont.
• Covalent Bonds – When electrons are shared between
atoms (These are called COMPOUNDS!)
• Compounds are 2 different atoms that are bonded
together
• Ex –Sugar/Glucose – Molecular compound C6H12O6
Bonds Cont.
• Hydrogen Bonds: “Opposites Attract”
(positives and negatives)
COMPOUNDS / MIXTURES
• COMPOUNDS – 2 or more different
elements bonded together.
• MIXTURE –Two or more substances NOT
bonded together.
• SOLUTION – A mixture of two or more
substances evenly distributed throughout.
POLAR MOLECULES
• A molecule that has a positive / negative
side. Ex – water
»
H
H
»
O
Thus ions and other polar molecules dissolve easily
in water and non-polar molecules like oils float on the surface.
ACIDS AND BASES
• ACID – A solution with many hydrogen
ions …PH 0-6
• BASE – A solution with many hydroxide
ions ….. PH 8-14
2- Divisions within Chemistry
• 1. Organic Chemistry - The study of the
chemical reactions involving the carbon
atom! Ex - plastics, petroleum, synthetics
• 2. Inorganic Chemistry- non - carbon
chemical reactions….Ex- Salts, metals
Why is the Carbon Atom so
reactive??
• Carbon has an atomic
number of 6…..
–
–
–
–
6-protons
6-neutrons
6-electrons
2 electrons in the first
energy level and 4 in
the outer energy level!
– Thus it can bond with
up to 4 other atoms!
• Carbon can bond with
itself into long chains
or into ring
Hydrocarbons…..H~C
•
•
•
•
•
Methane - CH4………….
Ethane - C2H6………….
Propane - C3H8………..
Butane - C4H10……..
Octane - C8H18……..
• Long chains of hydrocarbons provide fuel for our bar-b-ques, lighters,
automobiles, and trucks, as well as many are found in living
substances!!
Biochemistry
• The carbon compounds relating to
life……..
• Many carbon chains fold back upon
itself to form flexible rings!
• The arrangement of these rings can
encourage various types of bonding!
Functional Groups found in
Biological Compounds• . Methyl-(CH3)… found in fats oils, waxes
• . Hydroxyl- (-OH)…sugars and alcohol
• .Carboxyl- ( HOC=O) ..sugars, fats, amino
acids
• Amino- (-NH2)…Amino acids and
proteins
• Phosphate- (-PO4)…phospholipids,
DNA,RNA
4 - Molecules of Life!!
• 1. Carbohydrates- sugars and
starches!
• 2. Lipids- fats, oils and waxes!
• 3. Proteins - meat, poultry, eggs, soy
• 4. Nucleic Acids- building blocks for
DNA-”your genes!!”
CARBOHYDRATES“the watered carbons”
• Composed of C, H, and O…..with a 2:1
•
•
•
•
ratio of H to O!
3-types of Carbohydrates
1.Monosaccharides
– These are the buildimg blocks for
larger carbohydrates!
Formula C6H12O6
Ex-glucose, fructose, galactose
Carbohydrates continued…….
• 2. Disaccharides
– A short chain of a few monosaccarides
bonded together !!
– Formula: C12H22O11
– Only two bonded together makes up a
disaccharide!
– Ex: Sucrose, Lactose, Maltose
Carbohydrates….cont…...
• 3. Polysaccharides– Many “monos”
bonded together
forming a very
long chain!
– Ex- starch,
cellulose, and
glycogen
Condensation / Hydrolysis
• Condensation - When two molecules bond together
releasing one molecule of water during the process!
• C6H12O6 + C6H12O6
•
------------->C12H22O11 + H2O
• Hydrolysis - When a long chain of molecules are
broken apart requiring water to separate !
• C18H32O16 + 2H2O -------->
•
C6H12O6 + C6H12O6 + C6H12O6
PROTEINS……..
• The most diverse biological molecule of
life! – Examples - muscles, feathers, cartilage, enzymes,
steroids, hormones.
• The basic structural unit of protein is the
Amino Acid!
• These are bonded by condensation forming
long chains of polypeptides! ( proteins)
How are proteins structurally
different??
• There are 20 different common amino acids
needed for good health!
• The Basic structure of the Amino Acid is:
•
H
–
Amino
–
–
–
Group
Carboxyl
C
R- Group
Group
LIPIDS…….
• LIPIDS- serve as the main reservoir of
stored energy!
• Also a major component of cell
membranes!
• The basic Building Block of a lipid is the
“Fatty Acid”- usually a nonpolar molecule!
Fatty Acid Structure
• A Fatty Acid molecule is a long chain of ---CH2- CH2- CH2- CH2- CH2- CH2- CH2- CH3
• Attached to the front end is a CARBOXYL
•
•
•
•
•
H-O
|
C=O
|
H-C-H ( beginning of fatty acid chain)
Lipids cont……….
• Saturated fats - Long chain of fatty acids
with only single bonds!
• Unsaturated fats- long chains of fatty acids
with a few double bonds on the
hydrocarbon chain!
• Polyunsaturated fats- Many double bonds
on the hydrocarbon chain!
Neutral Fats - TRIGLYCERIDES
• Butter, lard and oils are examples !
• Three fatty acid chains bonded to a
GLYCEROL molecule!
•
H
–
H - C - OH
+ fatty acid chain
–
H - C - OH
+ fatty acid chain
–
H - C - OH
+ fatty acid chain
»
H
» ** Just under the skin, adipose tissue
stores lipids for energy and insulation!
PHOSPHOLIPIDS
• Two fatty acid chains bonded to a glycerol
and a phosphate group!
• This causes the molecule to have a polar
head and two non-polar tails!
• This is the main component of the cell
membrane!!!!
•
•
•
•
O
H
O -P-O ---- C - OH–
–
–
–
–
–
O
O
HO-C - CH2- CH2- CH3
O
H - C - OHH - C - OHH
HO-C - CH2- CH2- CH3
NUCLEIC ACIDS
• Nucleotides are the building blocks of
nucleic acids!
• Two important nucleic acids are
• DNA – 2 strands twisted together
• RNA – 1 strand of nucleotides
DNA and RNA
• These two molecules are essential for
survival!
• DNA forms into genes and
chromosomes directing the entire
chemistry of the cell!
• RNA produced from DNA directs the
making of proteins within the cell!
ATP….
• ATP - adenosine phosphate is the main
energy transfer molecule within the
cell!
Nucleotide structure
•
NH2
•
•
•
•
•
•
•
•
•
•
C
HC
HC
N
C=O
N
O
HO-P-O-CH2
O
C
C
C
OH
C
C
H
….el fin….